Imagine you’ve just bought a delicious smoothie from your local café. You like the smoothie so much that you want to know the recipe so that you can make it again at home whenever you want. You’re too shy to ask at the café, so you pour the smoothie through a series of special sieves that separate out each of the ingredients and you write down the recipe – 100ml orange juice, 50ml mango juice, 50ml banana purée and a handful of hipster kale (we haven’t tried this recipe, but we’re sure it would be lovely). You’re quite keen to keep drinking the smoothie, so you mix all the separated ingredients back together again, and the smoothie is just as delicious as before. Continue reading →
How many samples do you hope to collect on your next field assignment? 50, 100 or 1000? How about billions. It may seem overly optimistic, but that’s the reality when using Light Detection and Ranging, or LiDAR.
LiDAR works on the principle of firing hundreds of thousands of laser pulses a second that measure the distance to an intercepting surface. This harmless barrage of light creates a highly accurate 3D image of the target – whether it’s an elephant, a Cambodian temple or pedestrians walking down the street. LiDAR has made the news over recent years for its ability to unearth ancient temples through thick jungle, but for those of us with an ecological motive it is the otherwise impenetrable cloak of vegetation which is of more interest.
“In some years, chum salmon are frequently the bycatch of pollock fishermen” in the Bering Sea, Garvin explained. “Genetically, chum salmon that originate in Western Alaska tend to look very similar. This makes it difficult for stakeholders because management and conservation efforts to address this bycatch can differ among these regions, but the ability to identify them with genetics is not possible.” Continue reading →
In the UK, National Tree Week (26 November – 4 December) celebrates tree planting within local communities. The latest BES cross-journal Virtual Issue contains recent papers that highlight the global importance of trees and forests as habitat – for species from insects to primates – and in meeting human needs for fuel and agriculture. The selected papers also demonstrate novel methods scientists are using to study trees and forests.
National Tree Week is the UK’s largest tree celebration. It was started in 1975 by the Tree Council and has grown into an event that brings hundreds of organisations together to mark the beginning of Britain’s winter tree planting season.
Landscape connectivity is important for the ecology and genetics of populations threatened by climate change and habitat fragmentation. To begin our Virtual Issue Rayfield et al. present a method for identifying a multipurpose network of forest patches that promotes both short- and long-range connectivity. Their approach can be tailored to local, regional and continental conservation initiatives to protect essential species movements that will allow biodiversity to persist in a changing climate. The authors illustrate their method in the agroecosystem bordered by the Laurentian and Appalachian mountain ranges, that surrounds Montreal.
By charting the slopes and crags on animals’ teeth as if they were mountain ranges, scientists at the Smithsonian’s National Museum of Natural History have created a powerful new way to learn about the diets of extinct animals from the fossil record.
Understanding the diets of animals that lived long ago can tell researchers about the environments they lived in and help them piece together a picture of how the planet has changed over deep time. The new quantitative approach to analysing dentition, reported on 21 November in the journal Methods in Ecology and Evolution, will also give researchers a clearer picture of how animals evolve in response to changes in their environment.
A 3D reconstruction of the teeth of a western gorilla (Gorilla gorilla).
X-ray micro-computed tomography – or µCT – is a technique that uses x-rays to create high resolution cross-sections of samples. Virtual 3D models can be made from these cross-sections without destroying the original samples. Micro-CT has important applications in medical imaging and, in the biomedical field, in vivo µCT allows researchers to make virtual 3D models of the skeleton and organs of live small animals. Three-dimensional models like these could provide insight into diseases and guide the development of medicines and therapies.
In vivo µCT holds three major advantages over other methods:
It allows for repeated measurements of small live animals at different times without having to sacrifice them.
It eliminates variation among individuals.
It can reduce the number of animals required to obtain statistically meaningful data.
A variety of commercially available µCT scanners that are optimised for scanning live animals are now available. The use of in vivo µCT in ecological and evolutionary studies, however, has greatly lagged behind its use in biomedical studies. Continue reading →
DNA dietary analysis is a non-invasive tool used to identify the food consumed by vertebrates. The method relies on identifying prey DNA in the target animals’ scats. It’s especially useful for marine animals such as seals and seabirds as it is difficult to watch their feeding events.
Most people assume that research equipment is expensive and complicated. But, it doesn’t need to be and the noise egg is a perfect example of this. It consists of a watertight container (as used by scuba divers) and the buzzer from a cellphone and does exactly what it says: it produces low frequency noise. This allows researchers to test the effect of noise on underwater life. It is a small, simple and cheap device that anyone can build.
Underwater noise is rapidly increasing due to, for example, boat traffic and offshore wind farms. This can lead to stress for animals and difficulties in communication. Just as people have a hard time communicating in a noisy pub, animals may struggle to get their messages across when background noise is high. A nice description of how animals use sound and how noise may affect this can be found at www.dosits.org
While there is some knowledge on the effect of noise on large aquatic animals, we still know very little about how fish and other small aquatic animals are affected. Such knowledge is vital for management of protected areas. It’s also important to know whether wind farms and boat traffic can affect reproduction in populations of underwater resources such as fish and mussels. The answers to these questions are likely to be species specific, so we’ll need data on a large number of species in different habitats. Continue reading →
Years of research on the evolution of ancient life, including the dinosaurs, have been questioned after a fatal flaw in the way fossil data are analysed was exposed by scientists from the universities of Reading and Bristol.
Studies based on the apparently flawed method have suggested Earth’s biodiversity remained relatively stable – close to maximum carrying capacity – and hinted many signs of species becoming rapidly extinct are merely reflections on the poor quality of the fossil record at that time.
However, new research by scientists at the University of Reading suggests the history of the planet’s biodiversity may have been more dynamic than recently suggested, with bursts of new species appearing, along with crashes and more stable periods.
Animals feeding at sea inherit a chemical record reflecting the area where they fed, which can help track their movements, according to a new study by scientists from the University of Southampton.
Chemical testing of the source of marine food products could be a powerful tool to help to fight food fraud, maintain healthy sustainable fish stocks or marine protected areas, and ensure consumer confidence in marine eco-labelling. Continue reading →